They initially targeted governments in the Global South and excluded North America, Europe, and other high-income countries (see http://www.olpcnews.com/use_cases/education/childrens_machin... for a summary of their thinking early on). This did shift over time, though.
Even NGOs were initially blown off - Negroponte initially said they'd only sell lots of no less than one million to governments directly. But when they didn't get any firm takers in the first couple of years of the project, they started loosening those requirements, which is how Paraguay Educa even got their foot in the door (with a project that initially only had 4000 laptops, later increased to around 10,000).
There was a rather badly-managed OLPC project in Birmingham, Alabama. I have a paper co-written with Mark Warschauer and Shelia Cotten on it - once my website is back up it'll be available here: https://morganya.org/research/Ames_OLPC_Birmingham.pdf
Interestingly, in Paraguay the kids who did use their XOs much at all generally installed another windowing system. There was a nice easy package that even not-very-tech-savvy kids could install, I think put up by a hacker group in Uruguay (I'd have to check my notes on that one) with instructions in Spanish, that also came with some simple videogames and a video/audio player. Sugar was really not designed for media consumption, and that's what interested many of the kids!
As with many projects, there was quite a range in acceptance/uptake! Language was certainly a factor (more rural schools - which were also poorer on average - tended to be more Guarani-centric), but I would say that based on my observations it was not the most significant factor for uptake at school or at home.
In the classroom, bigger factors that limited uptake were breakage, drained batteries (most classrooms had minimal charging capacity, and even that capacity had been installed by Paraguay Educa), uninstalled software, and lack of teacher time/resources to develop curricula and work around all of these issues. Paraguay Educa hired teacher trainers in early 2010 and had a rotating tech support team to help with these issues, and this extra staff made some headway, but that kind of ongoing cost wasn't something the small NGO could sustain, unfortunately. (I have a long discussion about funding for charismatic new projects vs. maintenance/sustainability of existing projects in the book - as with many tech projects, maintenance was certainly a big issue!)
Kids who used them at home did tend to be stronger in Spanish, but relatively few were using them much at all, Spanish-speaking or not. While I didn't see improvements in reading or math among those who were part of the project there between 2010 and 2013 testing (though the testing was really not my focus - the observations and interviews were - we still ran them), it's common in other 1:1 programs to have modest gains in literacy because enough kids are motivated to practice reading to make sense of what they encounter on the Internet.
I hope this helps! Happy to clarify or answer follow-ups!
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